Songbird Response to Forest Disturbance Due to Unconventional Shale Gas Development in the Marcellus-Utica Region: A Multi-Scale Analysis.

Abstract

In this study, I evaluated impacts of unconventional shale gas development, or the combined use of horizontal drilling and hydraulic fracturing (i.e., fracking), on forest land cover and breeding songbirds in the Marcellus-Utica shale region. Since 2005, extraction of natural gas from the Marcellus-Utica shale has increased exponentially in the central Appalachians, an area of high conservation value for global biodiversity. Although there has been an increase in research on the effects of shale gas development in the region, the industry is still relatively new in the eastern U.S. and much is still unknown about biological and environmental impacts. In Chapter 1, I summarize potential effects of unconventional shale gas development on regional forests, and review the literature on songbird responses to forest loss and fragmentation. I also outline the overall research objectives of this dissertation and provide a summary of chapter topics. In Chapter 2, I evaluated the effects of shale gas development on a heavily forested, longterm study site in northern West Virginia, from 2008–2015. Construction of gas well pads and linear infrastructure contributed to an overall 4.5% loss in forest cover at the site, a 12.4% loss in core forest, and a 51.7% increase in forest edge density. I evaluated the relationship between land-cover metrics and species richness within three avian guilds: forest-interior, earlysuccessional, and synanthropic, in addition to abundances of 21 focal species. Land-cover impacts were evaluated at two spatial extents: a point-level within 100-m and 500-m buffers of each avian survey station, and a landscape-level across the study area (4,326 ha). Although I observed variability in species-specific responses, I found distinct trends in long-term response among the three avian guilds. Forest-interior species richness declined at all points across the site and at points impacted within 100 m by shale gas but did not change at unimpacted points. Earlysuccessional and synanthropic species richness increased at all points and at impacted points but did not change at unimpacted points. In Chapter 3, I focused on spatial responses of focal songbird species to distance from shale gas development, at the same long-term study site in northern West Virginia (2008–2017). I found that more than half of the focal species evaluated showed sensitivity to distance from shale gas infrastructure. Several forest interior species occurred in higher abundances with increasing distance from shale gas, while a few forest interior gap specialists increased in abundance closer to shale gas. Early successional